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The effects of fluorination on amorphous indium gallium zinc oxide thin-film transistors and circuits fabricated on a polyimide flexible substrate were studied. Attributed to more effective passivation of donor defects for a given thermal budget, fluorination resulted in suppressed apparent short-channel effects and better uniformity of turn-on voltage with reduced negative shift after laser lift-off from a glass carrier substrate. As representative digital circuits, two-input four-output (2-4) decoders were fabricated and characterized to demonstrate the advantages of incorporating fluorination in the construction of circuit building blocks, leading to higher gain, wider noise margins, more tightly distributed transition voltage, and larger output swing.

Thin‐film transistors (TFTs) based on amorphous indium‐gallium‐zinc oxide channels with or without fluorination were fabricated. The sensitivity of their electrical characteristics to hydrogen exposure was compared. It is shown that TFTs built with fluorinated channels exhibit significantly improved intrinsic resistance against hydrogen‐induced degradation; hence, they are potentially better suited for integration with hydrogen‐containing devices such as photo‐diodes based on amorphous hydrogenated silicon and TFTs based on low‐temperature polycrystalline silicon. The observed improvement correlates well with a reduced population of oxygen‐related defects and reduced hydrogen incorporation in the fluorinated channels.

Amorphous indium-gallium-zinc oxide (IGZO) thin-film transistors (TFTs) with or without fluorinated channels were fabricated. The sensitivity of their electrical characteristics to hydrogen exposure was compared. It is shown that those built with fluorinated IGZO exhibit improved intrinsic resistance against hydrogen-induced degradation. Such improvement correlates well with the reduced incorporation of hydrogen in the fluorinated channels, as revealed by secondary ion-mass spectrometry. Fluorinated IGZO TFTs are better suited for integration with hydrogen-containing devices, such as photo-diodes based on amorphous hydrogenated silicon and TFTs based on low-temperature polycrystalline silicon.

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The application of a versatile, low-temperature thin-film transistor (TFT) technology is presently described as the implementation on a flexible substrate of an analog front-end (AFE) system for the acquisition of bio-potential signals. The technology is based on semiconducting amorphous indium-gallium-zinc oxide (IGZO). The AFE system consists of three monolithically integrated constituent components: a bias-filter circuit with a bio-compatible low cut-off frequency of ≈1 Hz, a 4-stage differential amplifier offering a large gain-bandwidth product of ≈955 kHz, and an additional notch filter exhibiting over 30 dB suppression of the power-line noise. Respectively built using conductive IGZO electrodes with thermally induced donor agents and enhancement-mode fluorinated IGZO TFTs with exceptionally low leakage current, both capacitors and resistors with significantly reduced footprints are realized. Defined as the ratio of the gain-bandwidth product of an AFE system to its area, a record-setting figure-of-merit of ≈86 kHz mm −2 is achieved. This is about an order of magnitude larger than the < 10 kHz mm −2 of the nearest benchmark. Requiring no supplementary off-substrate signal-conditioning components and occupying an area of ≈11 mm 2 , the stand-alone AFE system is successfully applied to both electromyography and electrocardiography (ECG).

A glass‐based micro‐display with pixel size (<3µm) has been fabricated and verified in this work using deformed helix ferroelectric liquid crystal. High contrast (over 600:1), fast response time (< 400µs) and continuous gray scale within 5V driving voltage are achieved in the prototype.